This project continues the quantitative determination of the behavioral effects of the inhalation of low levels of organic solvents that are typically found in the workplace. Body burdens and mortality are also assessed as a function of concentration of agent and exposure. From these data estimates of ambient levels of organic solvents that pose minimal risk of behavioral toxicity will be made. The behavioral effects of aliphatic hydrocarbons, ketones, ethyl acetate, volatile anesthetics and psychopharmacological agents will be assessed. Studies on acute behavioral effects of organic solvents will be extended to sub-acute and chronic exposures to toluene, carbon disulfide and chlorinated hydrocarbons. Efforts will be made to minimize variability and increase sensitivity primarily by manipulating behavioral variables. We have found, for example, that whether subjects were relatively mobile or stationary, significantly different dose-response relationships could result for some organic solvents but not others. Most studies have been conducted on mice.